Accepting more than two arguments allows in particular to add
anonymous modules, which are not associated to variables. In principle
the only ones that have to be non-anonymous are those that have more
-than one successor / predecessor and/or are inputs / outputs.
+than one successor/predecessor and/or are inputs/outputs.
### nn.DAG:setInput(i) ###
Save a dot file to be used by the Graphviz set of tools for graph
visualization. This dot file can than be used for instance to produce
-a pdf file with
+a pdf file such as [this one](https://fleuret.org/git-extract/dagnn/graph.pdf) with
```
dot graph.dot -T pdf -o graph.pdf